June 26, 2019 (The BMJ)
This large-scale study dove deep into attempting to find relationships between sleep traits and the development of breast cancer in women.
The study, headed by Dr. Rebecca Richmond from the University of Bristol, was published in BMJ, and surveyed over 500,000 participants from the UK Biobank.
This data was analyzed using multivariable regression and a sample mendelian randomization model to find correlation between various sleeping traits and breast cancer risk. Some traits that the study looked into were preferences to both morning and nighttime work, the average amount of time asleep per day, and insomnia symptoms.
The analysis found that morning preference consistently was inversely associated with breast cancer risk and suggested that increased sleep duration may have an adverse effect on breast cancer risk. Results for insomnia symptoms and breast cancer risk were inconclusive.
Dr. Richmond and her host of co-authors suggest that further research be done to better understand the relationships between sleep traits and breast cancer risk, but this study makes significant progress in understanding these relationships.